In the field of pain management and neurosurgery, certain surgical procedures often require the internal placement and passage of tubes or wires from the spine to an external drainage system, a drug infusion system, or an electrical power source. Passage is best made through a subcutaneous tunnel in order to reduce the possibility of local or generalized infection; as well as to provide a secure anchor to the skin in order to avoid dislodgement of the electrical wire lead, surgical drain, or any other elongated tangible entity.
Some representative procedures which routinely require tunneling for the subcutaneous placement of a device from the primary incision site are exemplified by and include the following:
(i) Short-term epidural or subarachnoid infusions of opioid drugs. These procedures are frequently performed in order to improve the quality of life for patients with terminal cancer or for patients with nonmalignant pain who require a “trial” (e.g., a temporary infusion) of such medications to determine eligibility for implantation of a permanent drug delivery pump.
(ii) The “trial” (i.e., temporary) infusions of intrathecal Lioresal (or other skeletal muscle relaxants) for control of severe spasticity.
(iii) The placement of a lumbar drainage tube to facilitate chronic closed CSF drainage. This is frequently used in neurosurgery to reduce intracranial pressure, and for the emergency or temporary relief of hydrocephalus. Complications such as infection, catheter kinking, and leakage of CSF around the tube may be obviated by a subcutaneous tunnel through which a segment of the catheter passes to an exit site.
(iv) When performing a spinal cord stimulator “trial”, subcutaneous tunneling and placement of electrical lead wires from the spinal incision to an external electrical power source may reduce the risks of infection and dislodgment. Spinal cord stimulators are often implanted in patients with chronic neuropathic pain.